The modern state strives to render this circle of trade both large and permanent by means of commercial treaties, customs-unions, trading-posts and colonies. Thus while society at home is multiplying its relations with its own land, the state is enabling it to multiply also its relations with the whole producing world. While at home the nation is becoming more closely knit together through the common bond of the fatherland, in the world at large humanity is evolving a brotherhood of man by the union of each with all through the common growing bond of the earth. Hence we cannot avoid the question: Are we in process of evolving a social idea vaster than that underlying nationality? Do the Socialists hint to us the geographic basis of this new development, when they describe themselves as an international political party? [Sidenote: Geography in the philosophy of history.] It is natural that the old philosophy of history should have fixed its attention upon the geographic basis of historical events. Searching for the permanent and common in the outwardly mutable, it found always at the bottom of changing events the same solid earth. Biology has had the same experience. The history of the life forms of the world leads always back to the land on which that life arose, spread, and struggled for existence. The philosophy of history was superior to early sociology, in that its method was one of historical comparison, which inevitably guided it back to the land as the material for the first generalization. Thus it happens that the importance of the land factor in history was approached first from the philosophical side. Montesquieu and Herder had no intention of solving sociological and geographical problems, when they considered the relation of peoples and states to their soil; they wished to understand the purpose and destiny of man as an inhabitant of the earth. [Sidenote: Theory of progress from the standpoint of geography.]